NonRectangularTransparency.java Source code

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Here is the source code for NonRectangularTransparency.java

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/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
//package org.eclipse.swt.snippets;
/*
 * Create a non-rectangular shell to simulate transparency
 * 
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 * 
 * @since 3.0
 */
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.Region;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class NonRectangularTransparency {

    public static void main(String[] args) {
        Display display = new Display();
        final Image image = display.getSystemImage(SWT.ICON_WARNING);
        // Shell must be created with style SWT.NO_TRIM
        final Shell shell = new Shell(display, SWT.NO_TRIM | SWT.ON_TOP);
        shell.setBackground(display.getSystemColor(SWT.COLOR_RED));
        // define a region
        Region region = new Region();
        Rectangle pixel = new Rectangle(0, 0, 1, 1);
        for (int y = 0; y < 200; y += 2) {
            for (int x = 0; x < 200; x += 2) {
                pixel.x = x;
                pixel.y = y;
                region.add(pixel);
            }
        }
        // define the shape of the shell using setRegion
        shell.setRegion(region);
        Rectangle size = region.getBounds();
        shell.setSize(size.width, size.height);
        shell.addPaintListener(new PaintListener() {
            public void paintControl(PaintEvent e) {
                Rectangle bounds = image.getBounds();
                Point size = shell.getSize();
                e.gc.drawImage(image, 0, 0, bounds.width, bounds.height, 10, 10, size.x - 20, size.y - 20);
            }
        });
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        region.dispose();
        display.dispose();
    }
}